Sixty-two compounds have been characterized by GC/MS and relative retention times in the essential oil ofSenecio ambavilla(Bory) Pers. produced from plant material growing in Réunion (Indian Ocean). The oil was found to be rich in allo-aromadendrene (40%) and α-pinene (14%). While accounting numerically for approximatively third of the total number of compounds present in the oil, the monoterpene compounds contributed less than 23% of the oil content. On the other hand 70% of the oil was sesquiterpenoid in nature. In addition, long chain aldehydes, eremophilane, phytol (a diterpene alcohol) and indene derivatives were also identified as minor constituents.